During the course of a typical well drilling operation, it is often necessary to transport sections or joints of pipe to and from the work platform or floor of the drilling rig. To lower a pipe to the ground in the usual manner, so-called "elevators" which are dependently coupled to the traveling block of the derrick's hoisting apparatus are releasably secure to the upper end of each pipe joint and the lower end of the pipe swung over and laid onto an inclined "skid board" which is positioned between the edge of the rig floor and suitable horizontal pipe racks on the ground. As the hoisting machine is operated to lower the pipe, it will slide down the skid board; and, once the elevators are released, the pipe is manually guided onto the pipe racks where it can then be rolled to a desired location. On the other hand, pipes are typically raised to the rig floor by securing a winch line or so-called "cat line" to the upper portion to a pipe joint and pulling it longitudinally up the skid board. Once the pipe is adjacent to the rig floor, the elevators are coupled to its upper end and the hoisting machinery is operated to raise the pipe in the derrick for movement into an upright storage rack.
It will be appreciated, therefore, that these typical pipe-handling procedures are extremely hazardous to those working around the drilling rig as pipes are being moved onto or off of the rig floor. Moreover, the lower ends of pipe joints are sometimes damaged during these pipe-handling operations.